Modern aircraft may utilize a gas turbine engine propulsion system. Weight and cost may be significant factors in designing components for the propulsion system. Additionally, components in the propulsion system may experience high temperatures. Aluminum and composite material systems are often used in this environment for their favorable qualities of strength versus weight. Some component designs require composite materials and aluminum materials to be fastened together. However, aluminum has a much higher coefficient of thermal expansion than many composite materials. At the temperatures experienced in some areas of the propulsion system, the differing coefficients of thermal expansion may result in significant loads at the location of fasteners between the aluminum and composite materials, which may damage the composite components unless they are sufficiently reinforced against these loads which usually means more weight and cost.